JPH03500426A - Method and device for feeding and cutting fiber bundles in the direction of a fixed blade and a movable blade - Google Patents

Abstract

A process for feeding fibres towards the fixed and mobile knives of a fibre cutter, such as a flock cutter, is provided which includes preparing a mattress of fibres aligned in a direction which is substantially perpendicular to the vertical plane of the knife so that the mattress of fibres takes the form of a band. The band is conveyed in a step-by-step manner towards the knives while supporting the band adjacent the fixed knife so that its lower face and its lateral side faces are supported by planer support surfaces having a dimension significant in relation to the length of sections of fibres being cut. The step-by-step conveying is effected by bringing the band to a temporary standstill in relation to the support surfaces as the fibres are advanced towards the cutter.

Description

[Detailed description of the invention] Method of feeding fibers to fiber cutting equipment and cutting equipment for application of this method The purpose of the present invention is to improve the fixed and movable blades of Ill cutting devices, especially flock cutting devices. There is a method for feeding fibers in this direction.

In known cutting devices, the fibers are cut at a centerline extending transversely to the direction of movement of the fibers. The direction of the blade by being sandwiched between a smooth cylinder that is driven to rotate around the These fibers are temporarily stopped by a pinch during cutting and are removed from the blade. Proceed upstream.

This mode of operation is characterized, on the one hand, in the vicinity of the generation line of the cylinder where the fibers face each other; Some of the fibers are only sandwiched by the cylinder and with respect to the smooth cylinder On the other hand, the slippage of the fibers formed by the fed fibers is unavoidable. Because the pine tress or band is free along its lateral edges, the fibers It has the disadvantage that it does not guarantee regular feeding. Irregularities in the feeding of these fibers may be relatively important only in fiber cutting equipment that cuts fibers into long length pieces However, the irregularity is particularly due to the length of the cut sawIFi pieces being always less than 1 ml. Flock cutting %fill becomes unacceptable.

The purpose of the invention is to correct this drawback and to provide a very precise feeding of the fibers. of particular interest where flock-cutting vitM is concerned, and m-fiber bands. of one of these fibers over the entire cross section of the fiber or pine tress. This ensures that the cut pieces remain constant during the cutting process. The object of the present invention is to provide a method having one and the same length up to the length of the length.

To this end, according to the invention, the method Prepare a pine tress of fibers aligned approximately perpendicular to the Riko's pine tress shows the shape of the band, while supporting said band near the fixed blade. It ensures a gradual conveyance of the band from the side towards the blade, thereby covering its base and its transverse are each supported by a flat surface area, the size of which is considered parallel to said direction. large compared to the length of the fiber fragment to be cut by cutting and at least 0.1 am. stepwise conveying and cutting the band according to the next cycle with respect to said surface area. and alternating movement of said surface area supporting the band. This is done by generating according to the direction and the amplitude of the fiber fragment being cut. Equal to one step corresponding to the length, the cycle ends when the movable blade is released from the band and If the surface part supporting the band is located furthest away from the fixed blade, one is fixed with respect to the other and a portion of the band is moved downstream from the fixed blade. support the band during the entire movement of the surface area at least in the direction of the fixed blade temporarily stopping the band on a surface area, the length of the band portion being the length of the fragment; , and in the area disposed between the trajectory of the movable blade and said surface area, the surface area temporarily stopping the band when they reach their position closest to the fixed blade; cutting the band by a movable blade, with respect to the surface area supporting the band; Releasing the band, remove the surface area from the fixed blade to the area furthest from the fixed blade. By displacing these surface areas to move them away from each other, the bands are exposed. stopping on a surface area and releasing the band in said area, the band stopping and releasing the band when the band is free in the area, or with respect to the surface area; Adjusted so that it always stops in this area when it is free with respect to the surface area. It's about being able to do something.

According to one preferred embodiment of the invention, synchronously with the movable blade and from the drive of the movable blade. , movement of said surface areas, stopping of the band with respect to these frontal areas as well as said areas Stopping of the band at is controlled.

The object of the invention is also a cutting device for the application of said method.

According to the invention, the cutting device has one fixed blade removably arranged on the support. a movable blade removably disposed on a support; carrying a band of fibers; One approximately horizontal fixture located approximately at the same level as the edge of the fixed blade at cutting H position a support and one movable support, the cross section of which is parallel to the longitudinal centerline of the band; It is U-shaped with a plane at right angles, and its inner surface supports the bottom and side surfaces of the band. in the extension of the end of the fixed support closest to the fixed blade. one movable support located approximately at the same level as the edge of the fixed blade; one located approximately parallel to the U-shaped core at a level higher than the It has a flat, rigid and movable plate, and the surface of the U-shaped core has a large surface area. slightly smaller than the product, so that said plate is formed by a movable support or A banded shape that can move approximately parallel to itself between the legs of the shape The claw is arranged between the movable support and the fixed blade, and the claw is arranged between the movable support and the fixed blade. two parallel chucks extending transversely with respect to the longitudinal centerline of the band of m-fibers. one of these chucks is fixed and approximately level with the edge of the fixed blade. the band is placed between these two chucks, and the cutting device is connected to the movable blade. continuously drives the movable blade to cooperate with the fixed blade according to a periodic motion. and alternating directions approximately parallel to the longitudinal centerline of the band. A device for driving a movable support in motion and, on the one hand, the longitudinal center of the band in a direction approximately perpendicular to the line and on the other hand approximately parallel to said center line; With a device for driving the alternating movement of the movable plate according to the longitudinal centerline of the band for driving the alternating movement of the movable chuck of the jaws according to a direction approximately perpendicular to the and a device for driving a movable support, a movable plate, and a movable chuck with jaws. is synchronized with the drive of the movable blade and in the course of one cycle of the movable blade, i.e. the fixed During each pass of the movable blade in front of the blade, the movable support reciprocates between two distal positions. In one position it moves from a fixed blade to distanced and in the second position it is close to the fixed blade and these two distal The distance of the positioning is equal to the length of the mu fragment to be cut, while the movable blade It continues to ride on the top surface of the band as it passes from its first position to its second position. on the other hand it accompanies the movable support during its movement and on the other hand it a movable support separated from the top surface of the band as it passes from a position to a first distal position thereof. body, so that the movable chuck of the claws, on the one hand, and the movable support on its second as soon as the movable support moves from its second distal position to its first rides on the top surface of the band while moving to the distal position of the the movable support occupying its first distal position; Immediately and as soon as the plate rests on the top surface of the band and said support is in this first position. The plate is moved away from the top surface of the band during passage from the position to its second distal position, and the plate remains constantly on the top surface of the band during movement.

Other details and special features of the invention are attached hereto and the method and cut according to the invention are described below. DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG.

1 to 7 show successive stages of the method according to the invention in one cutting cycle. FIG.

FIG. 8 is a schematic vertical projection of a cutting device for application of the method.

FIG. 9 is a partial view similar to FIG. 8, and shows the variation of cutting it illustrated in FIG. It is a figure showing an example of a form.

FIG. 10 is a partially cutaway perspective view showing details of the cutting device illustrated in FIG. 9. FIG.

FIG. 11 is a partial view showing details of the wind.

In the various figures, the same reference numbers indicate the same or similar elements.

The method according to the invention comprises a fiber cutting device, in particular a fixed blade 1 and a movable blade of a flock cutting iiN. is designed to feed the MIN in the direction of the moving blade 2, and it first passes vertically in the path 4. Fixing a pine tress of fibers 3 aligned according to a direction approximately perpendicular to the normal plane Prepare to pass through green 5 of blade 1, so that this pine tress will itself banish. It shows the shape of do 6. To transport the band toward the blade, support the band near the fixed blade 1. It is carried out in stages by each supported by a flat surface area 9, the dimensions of which are parallel to said direction. Considering that it is large compared to the length of the fiber fragment 10 to be cut, it is At least about 0.1 am. Said staged conveyance and cutting is specified below. According to the cycle of the Temporarily stopping the band 6 with respect to the surface area 9 in order to prevent and by causing alternating movements of the surface area [9] supporting the is carried out in one step, the amplitude of the movement corresponding to the length of the fiber fragment 10 to be cut. , the cycle begins with the movable blade 2 being separated from the band 6 and The surface area vL9 supports the band at the position where it is moved farthest from the fixed blade 1. (see Figure 1), one is fixed with respect to the other and one part of the band 11 downstream from the fixed blade as shown in FIG. The band 6 is aligned on the surface area that supports the band during the entire movement of the surface area in the direction 1. temporarily stopping, the length of the band portion is equal to the length of the fragment 1o, and the movable blade 2 These are shown in FIG. Temporarily stop the band when it reaches those positions closest to fixed blade 1, such as That is, the band is cut by the movable blade 2 (see Fig. 4), and the band 6 is supported. releasing the band 6 with respect to the surface area 9 (see FIG. 5), which displacing these surface areas 9 in order to move them away from the fixed blade 1 (FIG. 6); When the surface area ￥L9 reaches those positions farthest from the fixed blade and when the releasing the band 6 in said area 12 when the band 6 is at rest with respect to the surface area [9]; It is to be.

According to the invention, the band 6 is arranged periodically over the top surface area 29 of said band. Surface area by applying pressure that is distributed! Although suspended regarding 4!9, The stop of the band in said area 12 is supported by the bottom surface 7 and top surface 29 of said band. The method according to the invention is carried out by sandwiching the band while cutting the fibers to be cut. setting the amplitude of the alternating movement of said surface area 9 as a function of the length of; setting the stop of said band 6 with respect to the surface area 9 at and on the other hand. Setting the stop of band 6 in zone 12 as a function of the thickness of the lever band , the thickness of which remains approximately constant.

The band 6 has said surface area 9 whose width is designed to support its lateral sides 8. Prepared to approximately correspond to the separation interval. Optimize the performance of your cutting equipment Therefore, the distance separating these surface areas 9 is longer than the length of the blades 1 and 2. is also chosen to be slightly smaller. The alternating movement of the surface area 9 cuts the band 6! Fi Stepwise advancement into the device and temporary stopping of band 6 with respect to said surface area 9 The temporary stop of the band 6 in [12] is synchronized with the drive of the movable blade 2. controlled by the state.

Due to the high speed of the cutting device, considerable heating occurs on blades 1 and 2, and this heating can also lump and weld some 5iisi made of synthetic materials . In order to prevent this disadvantage, the method according to the present invention includes a fixed blade 1 and a movable blade 2. permanently cooling the supports 13 and 14 of the selected to have a large contact surface area.

The fiber cutting device schematically illustrated in the drawing and for application of said method comprises a support 1 3 and one fixed blade 1 and one removably attached to the support 14, respectively. movable blade 2 and a 1 which is approximately horizontal and places a band 6 of 11H to be cut. one fixed support 15, these fibers are aligned on said fixed support and the fibers are aligned on said fixed support. This helps to ensure that the fibers run approximately parallel to the direction in which they travel through the cutting device. Advantageously, said fixed support is connected to the edge 5 of the fixed blade 1 of the cutting device, one movable support 16 is placed approximately at the same level as , and its cross section is relative to the longitudinal centerline of band 6. It forms a U shape with perpendicular planes, and its inner surface is closest to the fixed blade 1. located on an extension of the end of the fixed support 15 approximately at the same level as the edge 5 of the fixed blade. This constitutes said surface area 9 which supports the bottom side 7 and lateral side 8 of the placed band. Ma In addition, the cutting device 1 is used to temporarily stop the band 6 with respect to the movable support 1θ. It is provided with two flat, rigid and movable plates 17, and the placing plate is a movable support 16. It is arranged parallel to the core of the U shape at a level higher than the level, and its surface area is large. However, the surface area of the U-shaped core 18 is slightly smaller than that of the U-shaped core 18, so that the plate 17 is flexible. between the legs 19 of the shape formed by the dynamic support 16 approximately parallel to itself; The movable support together with the plate 17 can be moved to the conduit in which the band 6 is arranged. form. The cutting device also includes a pawl 20 in the area 12; is li! between the movable support 16 and the fixed blade 1! and two chucks 21 and 22, the chucks being parallel and centered longitudinally on the band 6 of the tiAM. Extends transversely to the line. The chuck 21 is fixed and the edge of the fixed blade 1 5, but chuck 22 is located at approximately the same level as path 4, as previously described. I! ! The band 6 can move in a direction parallel to the straight upper surface. It is arranged between two chucks 21 and 22. In addition, the cutting device has a movable blade 2. In order to continuously drive the movable blade 2 to cooperate with the fixed blade 1 according to a periodic motion. A device 23 such as a motor 24 is provided to drive a rod/crank system 25 for this purpose.

In order to feed the band 6 in stages to the cutting device, the cutting device is operated in the longitudinal direction of the band 6. for driving the movable support 16 in alternating movements according to directions approximately parallel to the center line; Me device! 26, but the band temporality with respect to the surface area 9 in the area 12 The stop is approximately perpendicular to the longitudinal centerline of the band 6 on the one hand. Therefore, and on the other hand, the intersection of the movable plate 17 according to a direction approximately parallel to said center line A device 127 designed to drive the reciprocal movement and on the longitudinal centerline of the band 6 The movable chuck 22 of the claw 20 is driven to alternately move in a direction approximately perpendicular to the This is obtained by means of a device 28 designed to do so. Movable support body 16, movable plate 17 and the devices 126, 27 and 28 respectively driving the movable chuck 22 are synchronized. The movable blades 2 benefit from the drive devices 23 and are driven from these devices 23. generate profits. Furthermore, these devices 26, 27 and 28 are connected to one of the movable blades 2. In the course of a cycle, i.e. between each pass of said movable blade in front of the fixed blade 1, the movable blade The support 16 is driven to reciprocate between two distal positions; when it is close to the fixed blade 1 and in the case of a low-speed cutting device, it is in the band 6 is kept stationary during cutting, and in the first position it is kept away from the fixed blade 1; and these two distal positions are equal to the length of the 1iill fragment to be cut. It is designed to be Furthermore, these 81226.27 and 28 are movable on one side. A plate 17 is connected to the movable support 16 from its first position to its second distal position. It continues to ride on the top surface 29 of the band 6 as it passes and accompanies it during its movement. , and on the other hand a movable support that moves from its second position to its first distal position. When it passes to the top of the band, it remains apart from the top surface 29 of the band, thereby causing the claw 20 to The movable chuck 22 is arranged such that the movable support 16 reaches its second distal position. the movable support 16 in this second distal position. during possible stops and when the movable plate moves from its second distal position to its first distal position. During the passage, the movable plate 17 separates from the top surface 29 of the band, and the movable support on the other hand As soon as the body 16 assumes its first distal position, it moves away from the top surface 29 of the band and the plate. 17 rests on the top surface 29 of the band 6 and the support 16 is in this first position. plate 17 touches the top surface 29 of the band during movement of the band. Designed to be ridden constantly.

The m-line cutting device according to the invention cuts the amplitude of the alternating movement of the movable support 16. A device f30 is provided for setting the coarse fragment 10 as a function of its length. This alternation These devices designed to keep the amplitude of movement constant after it has been adjusted 130 has one fixed stopper 31 (see FIG. 8) on one side, and its position can be adjusted when the cutting device is assembled and adjusted, it is fixed the second distal portion of the movable support 16 by limiting its movement in the direction of the blade 1; It is designed to determine the position with high accuracy and its movement is Whatever the length of the fiber fragment 10, it is carried out under the pressure of at least one spring 57. The eccentric weight can be adjusted as a function of the length of the fiber fragment 10 to be cut and cut. an eccentric 56 for bringing the support 16 into its first distal position. It is designed to act on the support 16 against the spring 57.

In the form of the embodiment of the cutting device illustrated in FIG. 9, the amplitude of the alternating movement of the movable support 16 is The VR 130 for adjusting the Two levers 37 are hinged to the holder 16 and each cooperates with the lever 37. and two fixed stoppers 32, whose positions are set according to the length of the coarse piece 1o to be cut. As a function of the spring 57, the lever 37 These levers 37 are pressed by two cams 56 acting on them. Stopper 3 2 and cam 56 are arranged on both sides of the lever 37, and these stoppers 32 are arranged on both sides of the lever 37. It is arranged on the support 16 and said cam 56 between 37 hinges 58 . cam 56 A spring 6o is provided to keep the lever 37 constantly pressed against the lever 37.

Each of the fixed stops 32 also has the benefit of an O-ra, the axis of which is The arm is suspended by the action of a device 33, such as a micrometer ratchet. These microspheres can be displaced for the positioning of the rollers according to the The chromator ratchet controls two arms 59 supporting two stops 32, They may be controlled simultaneously from one single control unit not shown here. It is combined with sea urchin. The axis of the roller constituting the fixed stopper 32 is at the working position (i.e. at their portion 56') and as a function of the length of the fiber fragments to be cut. Whatever the position of the roller as a number, it passes through the longitudinal centerline of the lever 37. placed in a plane parallel to the plane.

In addition to the device 30 for adjusting the amplitude of the movement of the support 16, the cutting device according to the invention comprises: Designed on the one hand to set the position of the movable plate 17 with respect to the movable support 16; The movable chuck 22 of the claw 20 is connected to the fixed chuck 21 on the other hand. 11 miscellaneous vans transported in stages by a movable support 16 a distance that can be separated from De 6 thickness.

and a device 35 for setting as a number.

In the form of the embodiment of the cutting device illustrated in FIGS. 8 and 9, the movable support 16 is At the end 36 of the rod 37', which is part of the device 26, there is actually a horizontal movement. The rod is supported and hinged so that it can be driven by the rod, the centerline of which is Pivoting on a fixed spindle 39 extending at right angles to the direction of displacement of the dynamic support 16 It has the other end 38 that can be freely assembled. In the form of the embodiment illustrated in FIG. The moving plate 17 is suspended on the one hand by the end 40 of the first set of cranks 41 and is hinged. The other end 42 is connected to a crossbar disposed above the movable support 16. hinged about an axis 43 parallel to the spindle 39 on a lateral 44 of 45; This crossbar can move approximately vertically and horizontally 44 The two parts 47 and 48 that respectively constitute the side plates of the crossbar 45 were selected. The height is adjusted by means of said device f34 consisting of a screw 46 which makes it immovable in position. and the movable plate 17 on the other hand via the second set of cranks 49. The cranks of the second set are fixed to the movable support 16 by the movable plate 17. This support 1 is hingedly connected to the shaft and around an axis parallel to the axis of the first set of cranks. These two sets are hinged at 51 to a lion-shaped leg 19 forming a The cranks 41 and 49 of are part of the device 27. Cutting equipment illustrated in Figure 9 In the embodiment of the present invention, the movable plate 17 is formed by the movable support 16 or has a shape. The ends of one set of cranks 41 on the other hand so as to always remain parallel to the core 18 40 and the other end of the crank is adjustable in height and a crosspiece movable in an approximately vertical position disposed above the movable support 16; - 44 and hinged about an axis 43 parallel to said spindle and on the other hand. through a set of deformable parallelograms whose axes are parallel to the axes of the set of cranks 41. The two planes of each of these deformable parallelograms are fixed to the dynamic support 16. The row elements 61' and 61'' are arranged at right angles to the U-shaped core 18 and along the band. 6 to the U-shaped leg 19 and to the navel of the movable plate 17. Each is installed. Regarding the movable chuck 22 of the jaw 2o, it is supported by the frame 52 and its height can be adjusted by the frame 52, The frame can move approximately vertically and is moved by a crank 53. the crank has a centerline parallel to the spindle 39; and is the part of the device 28 that is hinged to a fixed pivot 54.

Moreover, the said mountings 126, 27 and 28 cause the movement of the movable support 16. In order to a frame 52 for moving the movable support 16 from its second distal position. to its first distal position and the movable plate 17 is held by the movable support 16. The cross spar 45 is displaced so as to be separated from the top surface 29 of the band 6 which has been The frame 52 is moved so that the pawl 20 opens through the cam, and the cam is (Fig. 8) and parallel axes (Fig. 9). ), the parallel axes are connected to the drive device 23 of the movable blade 2 in synchronization with the movable blade 2. rotationally driven around the centerline and at the cross spar 45 and to the frame 52. (FIG. 9) or the movable support 16 (FIG. 8). ), the movements of the movable support 16, cross spar 45 and frame 52 are occurs in the opposite direction when no longer propelled by the cam and moves said movable support 16 for returning to its second distal position (FIG. 8) and for returning to its first distal position. (FIG. 9), the movable plate 17 rests on the top surface 29 of the band 6, and the claw 20 returns to the top surface 29. It is in the closed position by the action of screws 57, 57' and 57''.

Fixation to ensure cooling of blades 1 and 2 to prevent fiber adhesion or welding The supports 13 and 14 of the blade 1 and the movable blade 2 are designed to have a large contact area with the blades. designed, and said supports 13 and 14 each have at least one channel. 58, the channels extending along the length of the support and communicating cooling fluid. let A device, not shown here, is arranged on the support for this cooling fluid on the one hand. for conveying the fluid to one end of the channel 58 and for collecting the fluid at the other end of the channel. and on the other hand preferably continuously passing said cooling fluid through an inlet 58. It is provided for circulation.

As shown in FIG. 11, the pivot 54 to which the crank 53 is hinged is connected to the Gains that can be adjusted into position according to a direction parallel to the longitudinal centerline and thereby adjusting the position of the movable chuck 22 of the jaws 2o on the one hand. , thereby making it possible to stop the band in the immediate vicinity of blades 1 and 2. Place it as close as possible to the orbit of moving blade 2, and on the other hand, fix it so that 1 remains as long as possible. The position of the movable chuck 22 is changed as the movable chuck 22 is worn out. This axis 54 is adjusted by moving the slide block 67 that supports the pivot 54 in the fixed slide 65 with a spring. This is achieved by applying an action to the screw 64 which causes it to move against the screw 66.

It is understood that the invention is not limited to the embodiments described and that many modifications are within the scope of the invention. It is to be understood that embodiments may be made without exceeding.

international search report International Search Report BE 8800026

Claims (1)

[Claims] 1. Fixed blade (1) and movable blade (2) of fiber cutting equipment, especially flock cutting equipment A method for picking up fibers in a direction, the method comprising: picking up fibers (3) aligned according to a direction approximately perpendicular to a vertical plane passing through an edge (5) of a fixed blade (1); A mattress is provided, whereby the mattress assumes the shape of a band (6) and supports said band in the vicinity of the fixed blade (1) while maintaining a gradual conveyance of the band towards the blade. a fiber section whose bottom surface (7) and its lateral surface (8) are each supported by a flat surface area (9) and whose dimensions are cut when viewed parallel to said direction; large and at least 0.1 ■■ compared to the length of the piece (10), and the stepwise conveying and cutting causes the band to temporarily stop with respect to the shearing surface area (9) according to the next cycle and the band (6) by causing an alternating movement of said surface areas (9) supporting said fibers according to said direction, the amplitude of which is equal to one step corresponding to the length of the fiber segment (10) to be cut, said cycle assumes that the movable blade (2) is separated from the band (6) and the surface portion (9) supporting the band is in the furthest position from the fixed blade (1), one with respect to the other. fixed and In order to move a portion of the band (6) from the fixed blade to the lower bay, the band ( 6) temporarily stopping the band (6), the length of the part of said band (6) being equal to the length of the fragment and being located between the trajectory of the movable blade (2) and said surface area (9); in the area (12) where the surface area reaches those positions closest to the fixed blade (1). temporarily stopping the band, cutting the band with the movable blade (2), and releasing the band (6) with respect to the surface area (9) supporting the band. and displacing these surface areas (9) in order to move the surface areas away from the fixed blade (1) to their position furthest away from the fixed blade (1); 9) stopping on and releasing the band (6) in said area (12), stopping and releasing the band (6) on the surface area when the band is free in the area (12). (9) or if it relates to surface area (9) is controlled so that it always stops in this area (12) when it is free to How to make it a sign. 2. The amplitude of the alternating interlocking of said surface areas (9) is a function of the length of the cut segment (10). 2. A method according to claim 1, characterized in that the method is adjusted as a number. 3. The stop of the band (6) is adjusted with respect to the surface area (9) supporting it, and the stop of the band in said area (12) is adjusted as a function of the thickness of the band, which remains approximately constant. The method according to any one of claims 1 and 2, characterized in that: 4. Claim 1, characterized in that the movement of the surface area (9) as well as the stopping of the band in the area (12) is controlled synchronously with the movable blade (2) and from the drive of the movable blade. The method according to any one of paragraphs 3 to 3. 5. The ribbon (6) has a surface area designed such that its width cooperates with its lateral surface (8). The method according to claims 1 to 4, characterized in that the arrangement corresponds approximately to the distance separating the zones (9), and that this distance is slightly less than the length of the blades (1, 2). The method described in any one of the above. 6. Choosing a support which cools the supports (13, 14) of the fixed blade (1) and the movable blade (2) of the cutting device, preferably in a continuous manner, and which exhibits a large surface area in contact with the blades. The method according to any one of claims 1 to 5, characterized in that: 7. A fiber cutting device, in particular a flock cutting device, for the application of the method according to any one of claims 1 to 6, which cutting device is removable to a support (13). one fixed blade (1) arranged on the support (14), one movable blade (2) removably arranged on the support (14) and the edge of the fixed blade (1) on which the band of fibers rests and of the cutting device. one approximately horizontal fixed support (15) located approximately at the same level as (5) and one movable support (16) whose cross section is relative to the longitudinal centerline of the band (6). the surface area (9) which supports the bottom (7) and side surfaces (8) of the band; In the extension of the end of the body (15), the edge (5) of the fixed blade and the one movable support (16) arranged at the same level and one flat, rigid and a movable plate (17), said plate having a large surface area and slightly smaller than the surface area of the U-shaped core (18), such that said plate (17) is formed by a movable support (16); between itself and the U-shaped legs (19). A band (6) is placed between the U-shaped core and the plate, and one pawl (20) is placed between the movable support (16) and the fixed blade (1). The fibers are arranged in such a way that they form two parallel chucks extending transversely with respect to the longitudinal centerline of the fiber band. (21, 22), one of these chucks (21) is fixed and located approximately at the same level as the edge (5) of the fixed blade (1), and a band (6) connects these two chucks (21). , 22), and the cutting device is arranged so that the movable blade follows the periodic motion. a device (23) designed to continuously drive the movable blade (2) in cooperation with the fixed blade (1) and in a direction approximately parallel to the longitudinal centerline of the band (6); subordinate a device (26) for imparting an alternating motion to the movable support (16), on the one hand in a direction approximately perpendicular to the longitudinal centerline of the band (6) and on the other hand forward; a device (27) for imparting alternating motion to the movable plate (17) according to a direction approximately parallel to the center line; and a movable chuck (22) of the claw (20) according to a direction approximately perpendicular to the longitudinal center line of the band. ) and a device (28) for giving alternating motion to the Furthermore, the device (26, 27, 28) for driving the movable support (16), the movable plate (17), and the movable chuck (22) of the claw (20) is the drive device (23) of the movable blade (2). and in the course of one cycle of the movable blade, i.e. during each pass of the movable blade in front of the fixed blade (1), the movable support (16) reciprocates between two distal positions. It is designed to be made to perform cut and in the second position it is close to the fixed blade, the distance between these two distal positions being equal to the length of the fiber fragment (10) to be cut, while the movable blade (17) when passing from a first position to its second position it continues to ride on the top surface (29) of the band (6) and accompanies the movable support (16) during its movement; and On the other hand, it accompanies the movable support away from the top surface (29) of the band as it passes from its second position to its first distal position, thereby causing the movable chuck (20) of the pawl (20) 22) on the one hand as soon as the movable support reaches its second distal position and the movable support moves from its second distal position to its first distal position; during the movement rests on the top surface (29) of the band, the movable plate (17) is then moved away from the top surface (29) of the band (6), and on the other hand the movable support (16) is placed on its first as soon as the plate (17) rests on the top surface of the band. and during the passage of said support (17) from this first position to its second distal position, the plate (17) is moved away from the top surface (29) of the band (6), during this movement. van A fiber cutting device, characterized in that it remains constantly on the top surface (29) of the fiber cutting device. 8. 3. The fiber cutting device according to claim 1, characterized in that the fiber cutting device comprises a device (30) for adjusting the amplitude of the alternating movement of the movable support (16) as a function of the length of the fiber segment (10) to be cut. The fiber cutting device according to item 7. 9. Claim 1, characterized in that the device (30) for adjusting the amplitude of the alternating movement of the movable support (16) is constructed in such a way that, when the amplitude is set, the amplitude remains constant. The fiber cutting device according to item 8. 10. The fiber cutting device comprises devices (34 and 35) for setting the position of the movable plate (17) and of the movable chuck (22) of the claw (20) as a function of the thickness of the band (6) of fibers to be cut. ) The fiber cutting device according to any one of claims 7 to 9. 11. The device (30) for setting the amplitude of the alternating movement of the movable support (16) the second distal position of the carrier (16) to limit its movement in the direction of the fixed blade (1); and one fixed stop (31) arranged to determine the displacement. Whatever the length of the fiber fragments (10) to be cut, at least one movement of this support into its first distal position, with an eccentricity that can be adjusted as a function of the length of the fiber fragment (10) to be cut; is arranged to act on the support (16) against the spring (57) in order to Fiber cutting device according to any one of claims 9 and 10, characterized in that it comprises an eccentric body (56) located thereon. 12. The device (30) for setting the amplitude of the alternating movement of the movable support (16) is two levers (57) hinged to the support (16) symmetrically with respect to the longitudinal centerline of the hand (6) and two fixed struts each cooperating with one lever; a stopper (32), the position of which can be adjusted as a function of the length of the fiber fragment (10) to be cut, whereas the levers are provided with springs (57) acting on these levers; applied by two cams (56), the stopper (32) and the cam (56) being arranged on either side of the lever (37), the stopper (32) - (37) between the hinge part (58) on the support (16) and the cam (56), the spring (60) holding the lever (37) applied against the cam (56). vinegar The fiber cutting device according to any one of claims 9 and 10, characterized in that the device is provided for cutting. 13. Each of the fixed stops (32) consists of a roller, the axis of which is supported by an arm (59), which adjusts the position of the roller according to the vertical direction by the action of a device (33), such as a micrometer ratchet. These micrometer ratchets can be controlled at the same time. The axes of the rollers constituting the fixed stop (32) control two arms (59) that support two stops (32) joined together to whatever their position in the working position and as a function of the length of the fiber fragments to be cut, be arranged in a plane parallel to the plane passing through the longitudinal centerline of the lever (37). A fiber cutting device according to claim 12. 14. A movable support (16) is supported on the end (36) of the rod (37') and The other end (38) is hinged to the movable support (16) in the direction of displacement of the movable support (16). and mounted on a fixed spindle (39) of a centrifugal axis, the movable plate (17) being suspended on the one hand and hinged to the ends (40) of the rods (41) of the first set; The other ends (42) of the rods of the first set are movable according to an approximately vertical direction, are adjustable in height and are arranged above the movable support (16) by a crossbar (45). the movable plate is hinged about an axis (4 3) parallel to said spindle (39) at , and said movable plate extends on the other hand to a ramp (17) and a U-shaped leg (19) constituting a movable support (16). ) to the movable support by means of a second set of rods (49) with axes parallel to those of the first set, which are hinged to the The movable chuck (22) of the pawl (20) is connected by a rod (53) of an axis parallel to said spindle (39) and hinged to a fixed pivot (54). Claims 7 to 13, characterized in that it is supported in a height-adjustable manner at its ends by a movable frame (52) which is itself supported according to an approximately vertical direction. The fiber cutting device described in . 15. A movable support (16) is supported on the end (36) of the rod (37') and The other end (38) is hinged to the movable support (16) in the direction of displacement of the movable support (16). The movable plate (17) is suspended on one side and hinged to the ends (40) of a set of rods (41), and the other end is attached to a fixed spindle (39) with an angled axis. (42) is movable according to an approximately vertical direction, adjustable in height and arranged on a crossbar (45) arranged above the movable support (16) with an axis parallel to said spindle (39). Hinged around (43) and said movable plate is on the other hand linked to a movable support by a set of deformable parallelograms (61) whose axes are parallel to the axes of said set of rods (41). The two parallel elements (61') of each of these deformable parallelograms are perpendicular to the U-shaped core (18) and in the longitudinal direction of the band (6), respectively. Attachment symmetrically with respect to the core to one of the U-shaped legs (19) and to the movable plate (17) The movable chuck (22) of the claw (20) is hinged to the fixed pivot (54). itself by means of a rod (53) with an axis parallel to said spindle (39) The movable frame (52) supported along the vertical direction The fiber cutting device according to any one of claims 7 to 13, characterized in that the fiber cutting device is supported so that its height can be adjusted. 16. The movement of the movable support (16), the movement of the crossbar supporting the movable plate (17) and the movement of the frame (52) supporting the movable chuck (22) of the claws (20) are controlled by the movable support. (16) from one of its distal positions to the other, the movable plate (17) is moved away from the band supported by the movable support (16). In order to move the crossbar (45) and open the claw (20), the frame (52) is connected to the movable blade by a cam (55, 56) rotationally driven by the drive device (23) of the movable blade (2). in order to move in synchronization with the lever (37). acts on the movable support (16), on the crossbar (45) and on the frame (52), such that the movement of said movable support, crossbar and frame causes said movable support (16) to move in its distal position. The movable plate (17) rests on the band (6) and pawl (20) in the closed position respectively by the action of the return springs (57, 57', 57''). Claims 14 and 14 are characterized in that 16. The fiber cutting device according to any one of Items 15 and 15. 17. The supports (13 and 14) of the fixed blade (1) and movable blade (2) have large contact with the blade. the support has at least one channel (58) extending along the length of the support and designed to allow passage of coolant; one end of a channel (58) formed in the support on the other hand; an arrangement for moving and collecting this coolant on the one hand and preferably continuously circulating said coolant through said channels (58) on the other hand; The fiber cutting device according to any one of claims 7 to 16, characterized in that a fiber cutting device is provided with a fiber cutting device. 18. Said fixed pivot (54) on the one hand adjusts the position of the movable chuck (22) of the claw (20) so that it is as close as possible to the trajectory of the movable blade (2) so that it stops the band in the immediate vicinity of the blade; On the other hand, it is possible to The position of the movable chuck (22) is changed as the fixed blade (1) becomes increasingly worn. In order to be able to The fiber cutting device according to any one of claims 14 to 17, which can be adjusted to a predetermined position by adjusting the fiber cutting device.